Press and analysts get excited when a platform changes its reporting metrics, but when it comes to media buyers, they’re often left unfazed.

When Twitter swapped its reporting of monthly active users (MAUs) for monetizable daily active users (mDAUs), a chart from Recode showed just how small Twitter’s overall daily audience is when compared to Facebook and Snapchat.

But for buyers, it’s business as usual. Addressable reach is exactly how buyers have always defined and evaluated platforms, among other factors like demographics, interests and campaign effectiveness. Those numbers are easily identifiable via the platforms’ self-serve ad buying tools.

“DAU, MAU is taken with a grain of salt. Platforms always tell you the best possible number from the best possible angle, like people who only show you pictures of themselves from their good side. Counting those people who only login once a month for two minutes isn’t being genuine about who we can reach,” said Duane Brown, founder and head of strategy at Vancouver-based agency Take Some Risk.

Tech platforms share whatever metric they think will put them in the best light, whether it’s Pinterest seeking investors for its initial public offerings or Facebook simply wanting to tout its massive scale even with all of its scandals. But media buyers look at those headlines as the never-ending flaunting of vanity metrics. Advertisers don’t need to scale their campaigns to all of Facebook’s 2.32 billion monthly active users. Buyers look at demographics, like age, location, household income and interests, and if they can reach them through a certain time period with a particular budget, said Lisa Reid, associate director, search and social at Mindshare.

“Comparing the scale is nuanced. From an advertiser standpoint, we use these numbers to support and directionally inform channel strategy and investment. However, once we are able to see where our audience is, we can rely on the platforms to tell us potential audience reach given a certain budget and flighting period,” Reid said.

That nuanced look at scale is one way Snap is trying to position themselves in the fight for survival (and advertisers’ budgets) against Facebook. Speaking at the Morgan Stanley conference on Feb. 25, Snap CEO Evan Spiegel said, “A lot of people are surprised when they actually look at the data and see the overlap for our audience, and the audiences of products built by competitors. For example, in our core markets like the United States, U.K. or France, we tend to have roughly the same audience size as products people perceive to have a much larger audience.”

For example, Snap’s self-serve ad tools show that the platform has 47 million users age 13 to 24 in the U.S. while Instagram has 33 million in that demo. Jordan Jacobson, vp, head of social media U.S. at iProspect, said he has to educate his agencies’ clients on these types of specifications.

“While the CMO might read the Wall Street Journal and call us and ask why Snapchat is still in the [media] plan, we have numbers to back it up and running brand studies to make sure it’s actually working. As it stands right now, that core [Gen Z] demographic is still there,” Jacobson said.

Of course, buyers don’t look blindly at the numbers provided by the self-serve tools. Veronica Ripson, a digital marketing consultant, said she and her peers use baseline discount factors such as about 40 percent on audience size for Facebook based on campaign date.

“Ideally, you record audience types, first, second, third party, and have discount factors for that or even more ideally; you’re tracking estimates versus delivery for specific audiences so you can use that, and it’s automated,” Ripson said.

John Max Bolling, marketing manager at Engine, said his agency will run tests on platforms, especially on Snapchat which is less trusted in its ability to scale. For example, if they see a good return on investment of a $10,000 campaign on Snapchat, they will invest more.

Buyers said they don’t necessarily care what metrics platforms use to impress investors in earnings calls. But they did want the platforms to better position themselves and not stretch their offerings. For example, Twitter had previously told buyers it was investing more direct-response ads. But over the last year, Twitter has committed itself to being a place for live events and real-time campaigns.

“What the platforms need to do is really home in on their sweet spot and know where they can have success in versus positioning themselves against Facebook,” said Jacobson of iProspect. “It’s a lot easier to chat with them about solving real business challenges versus coming up with a pitch deck of their latest attempt.”